The heart of an astronaut actually gets smaller when in outer space.
216
Today's top fuel dragsters take off with more force than the space shuttle.
120
Pluto is smaller than Russia.
9
The earth travels through space at 660,000 miles per hour.
189
In the last 7 years, humanity has discovered 43 potentially habitable planets.
14
Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46
The population of the Earth has more than doubled since 1950.
151
